GRE Subject Test: Chemistry : Electrochemical Analyses

Study concepts, example questions & explanations for GRE Subject Test: Chemistry

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Example Questions

Example Question #1 : Electrochemical, Environmental, And Other Analyses

Once a sample of DNA is isolated, it is loaded on an agarose electrophoresis gel, as shown below. Once the sample has run, where will the student find the DNA?

 

Agarose_gel

Possible Answers:

It is impossible to tell without knowing the charge of the DNA

Red section

Green section

It is impossible to tell without knowing the size of the DNA fragments

Correct answer:

Green section

Explanation:

DNA is negatively charged, so it will migrate toward the positive electrode during electrophoresis. As a result, it will migrate from the center line into the green region of the gel.

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